MandrakeSoft takes Perl very seriously because it is at the heart of the install process of their distro.
So here what Garcia-Suarez, a Perl pumpking who works at MandrakeSoft, said to me on #perlfr, modulo what has been "lost in translation".
I have filled a few blanks too.

The Mandrake distro is divided in 2 "media". The main media is supported by MandrakeSoft; contrib is not.
Additionally, there is update that contains security update.
Finally, there is plf, that
contains rpms packaged by the
Penguin liberation Front. These packages have a dubious or incompatible legal status that makes them ineligible for distribution by Mandrakesoft.

The core of Perl is split in 4 rpms: perl-base, perl-doc, perl, perl-devel.
The perl-base rpm contains a minimum perl distro useful in the boot process where the whole Perl would be too big.
The perl rpm is the rest of core perl minus perl-doc, that contains the doc and perl-devel that contains the C headers.

Rafael is the packager of Perl and of 119 Perl modules as testified by:
rpmmon -q rgarciasuarez@mandrakesoft.com | grep perl- | wc -l
Other Perl modules are packaged by other people.
The policy is to update immediately the update media
when there is a security update for a perl module.
Also, cooker, the experimental distro is fairly
up to date. I am using cooker and
does urpmi.update -a; urpmi --auto-select to keep
my host up to date and I regularly see Perl related updates in the logs.

There is a lot of stuff that is proper to Mandrake
but can be of a larger interest. For example
the MDK::Common package contained in the rpm perl-MDK-common.
The urpmi command is a Perl script that is updated by rgs almost daily (but this is relevant only for people under cooker).

Also, in the next major release MandrakeSoft will probably distribute the non threaded
version of Perl as default. The rational is that threaded Perl is slow and buggy.